diff --git a/src/sysyc.cpp b/src/sysyc.cpp
index 78930a0..4899858 100644
--- a/src/sysyc.cpp
+++ b/src/sysyc.cpp
@@ -70,6 +70,9 @@ void parseArgs(int argc, char **argv) {
         if (optLevel < 0) {
           cerr << "Error: Optimization level must be non-negative." << endl;
           usage(EXIT_FAILURE);
+        } else if (optLevel == 1) {
+          cerr << "debugging, exit..." << endl;
+          exit(-1);
         }
       } catch (const std::invalid_argument& ia) {
         cerr << "Error: Invalid argument for -O: " << optarg << endl;